Clutch Slipping

WARNING: This page is about a different variant/trim than selected.

Clutch Slipping

Cause	Action
DEFINITION: The clutch does not engage completely after the pedal is released, after shifting gears, or the clutch slips during maximum engine loads, such as climbing hills or high vehicle speeds. Clutch slipping is identified by increase in engine RPM without increase in vehicle speed. Review the Symptoms - Clutch and perform the necessary inspections.
Incorrect clutch pedal height, not allowing the clutch master cylinder to return	Faulty clutch start switch. Refer to Clutch Pedal Engine Start Switch Replacement .
The clutch pedal return spring is broken or missing	Replace the clutch pedal return spring, if equipped. Refer to Clutch Pedal Replacement .
The clutch pedal is binding or sticking	Clear away any items that may be contacting the pedal. Inspect the pedal bushings for ease of movement. Replace the clutch pedal if it is faulty. Refer to Clutch Pedal Replacement .
Clutch master cylinder binding or seized	Replace the clutch master cylinder. Refer to Clutch Master Cylinder Replacement .
Clutch actuator cylinder binding or seized	Replace the clutch actuator cylinder. Refer to Clutch Actuator Cylinder Replacement (NV3500/NV4500) or Clutch Actuator Cylinder Replacement (ZF S6-650) .
Kinked or damaged clutch hydraulic hose	Inspect for the correct routing of the clutch hydraulic hose. Route the hose properly. Inspect for loose or faulty engine mounts that may allow the hydraulic hose to be kinked or pinched. Repair or replace faulty engine mounts. Refer to Engine Mount Replacement - Left and Engine Mount Replacement - Right (4.3L), Engine Mount Replacement - Left and Engine Mount Replacement - Right (4.8L, 5.3L, and 6.0L), Engine Mount Replacement - Left and Engine Mount Replacement - Right (8.1L) or Engine Mount Replacement - Left and Engine Mount Replacement - Right (6.6L). Repair or replace the clutch hydraulic hose if it is damaged. If it is a 5 speed transmission, refer to Clutch Master Cylinder Replacement . If it is a 6 speed transmission, refer to Clutch Actuator Cylinder Replacement (NV3500/NV4500) or Clutch Actuator Cylinder Replacement (ZF S6-650) .
Grease or oil contamination of the clutch disc	Repair the source of the oil leak. Repair the source of the grease leak. Clean the contamination from the clutch components. If contaminates cannot be removed, replace the clutch assembly. Refer to Clutch Assembly Replacement .
Worn or damaged flywheel	Replace the engine flywheel. Refer to Engine Flywheel Replacement (4.3L), Engine Flywheel Replacement (4.8L, 5.3L, and 6.0L), Engine Flywheel Replacement (8.1L), Engine Flywheel Replacement (Automatic Transmission) or Engine Flywheel Replacement (Manual Transmission) (6.6L).
Worn clutch disc facing	Replace the clutch assembly. Refer to Clutch Assembly Replacement .
Clutch discs splines worn	Replace the clutch assembly. Refer to Clutch Assembly Replacement .
Low pedal from self-adjusted clutch adjusted forward	Replace the clutch assembly. Refer to Clutch Assembly Replacement .
Burnt or glazed clutch discs	Replace the clutch assembly. Refer to Clutch Assembly Replacement .
Input shaft splines worn	Replace the input shaft. Refer to TRANSMISSION DISASSEMBLE (NV 3500), TRANSMISSION DISASSEMBLE (NV 4500) or TRANSMISSION DISASSEMBLE (ZF S6-650).
Improper resurfacing of the flywheel	Replace the flywheel if it has been improperly resurfaced, allowing contact of the clutch disc hub or insufficient clamping load of the pressure plate. Refer to Engine Flywheel Replacement (4.3L), Engine Flywheel Replacement (4.8L, 5.3L, and 6.0L), Engine Flywheel Replacement (8.1L), Engine Flywheel Replacement (Automatic Transmission) or Engine Flywheel Replacement (Manual Transmission) (6.6L).